Direct current conductivity of evaporated cadmium selenide thin films

Current density-voltage characteristics have been obtained from thin films of CdSe, when sandwiched between ohmic gold and blocking aluminium electrodes. At low voltage, the current in the forward direction varies exponentially with voltage, and the transport mechanism is found to be dominated by recombination at the depletion region. At higher voltage, two distinct regions of ohmic and space-charge limited conduction dominated by a discrete trap level were observed. The thickness dependence in the square-law region has been found to confirm the d(-3) law. (C) 1999 Elsevier Science B.V. All rights reserved.